This invention relates to a mobile bed and chair combination for patients in hospitals, nursing homes, or similar health care facilities including the home in which the safe transfer of the patient from a hospital type bed is contemplated by a single healthcare giver.
There are various devices known in the art for transporting the disabled from one place to another. The most commonly known is the wheelchair either powered or non-powered. In the hospital and nursing homes, gurneys are used to transfers the patient from one place to another while remaining in a lying or prone position. Often it is necessary to transfer the patient from the hospital bed to a gurney type bed of wheelchair. Studies have shown that upwards to fifty percent of all injuries to either patients or healthcare people have occurred when the patient is being transferred from the bed to a gurney or to a wheelchair. That is, when a patient is transferred from a bed to a wheelchair, the patient must first be raised to a sitting position, rotated so that their feet are over the side of the bed, and then lifted form the bed to the chair. This usually requires three people for a safe transfer, two to lift the patient off the bed, and one to rotate the patient and gently guide him into the chair. Similarly, if the patient is to be transferred from a bed to a gurney, two and sometimes three people are required for a safe transfer, two to lift the patient and one to stabilize the gurney.
Unfortunately, the realities of the healthcare situation in our country and indeed over the world, have stretched the healthcare dollar so thin that many of our provider institutions can no longer provide the necessary personnel to ensure the safe transfer of patients in the above described situations. Instead of the two or three people required to perform the patient transfer, often only one is available. As is often the case, the patient is of a size or weight that is difficult for the healthcare giver to manage by him or herself. The result is either the patient is dropped or the healthcare person sustains a back injury. Such a state of affairs only exacerbates an already strained industry in terms of lost time and money for both the healthcare giver and institution; and the ill will of, or a lawsuit by, the patient should further injury result.
The prior art has attempted to relieve the situation by providing combination wheelchair and bed mechanisms. For example, the patent to Crawford et al, U.S. Pat. No. 5,402,544, discloses a combination chair and gurney which permits one device to operate both as a wheelchair and as a gurney. The object of Crawford et al is to attend to the bodily needs of a disabled person. In Crawford et al, the chair can be converted to a bed and then hand cranked to a height to correspond to a bed height. The mobile bed is then placed adjacent the bed and held stabilized by xe2x80x9celastic bungee cordsxe2x80x9d connected between the rails of the bed and the Crawford et al device (col. 5 line 25 of Crawford et al). The problem with Crawford et al is that there is still a gap between the two beds, and an uncomfortable obstacle in the form of the rails to negotiate in the patient transfer. Moreover, there is, over time, a very real possibility of the bungee cord breaking with disastrous consequences. Another patent t Ezenwa, U.S. Pat. No. 5,193,633, is designed in particular for paraplegics in a home environment. This patent also shows a chair converting to an adjustable height bed device, and, has a lateral shifting mechanism for use in the wheelchair mode so that the each of reaching over the head by the disabled can be effected. This lateral shifting is stabilized as to the center of gravity by a tilting of the chair toward the center of the wheeled platform. See FIGS. 6 and 7 of Ezenwa. Thus, while this feature is effective for the patient when he reaches high over his head to keep him stabilized, it is counterproductive to the transfer of the patient from the mobile bed to another bed because it presents both a gap between the beds and a raised obstacle therebetween (due to the tilting). This patent like Crawford et al above is seen to require at least two or maybe three people to effectuate a safe transfer of the patient. Another prior art attempt to address the problem of transporting patients from a bed to a convertible wheelchair/bed structure is disclosed by a patent to Jones, U.S. Pat. No. 4,119,342. In this patent, the wheelchair converts to a bed mode of a fixed height (equal to the height of the wheelchair arms). Thus, it is required that the bed in which the patient is lying be lower than this fixed height, so that the bed mode will then hang over the bed by up to seven inches to perform the transfer. This apparatus suffers from three drawbacks. One, the bed must be lower in height than the Jones device because the device is not adjustable; two, assuming the bed is lower, the obstacle created by the thickness of the platform structure (wheelchair arms and pad) would cause a difficult transfer procedure, if not insurmountable if the bed is even one or two inches below the Jones"" bed platform; and three, a seven inch overlap has been found by the inventors hereof to be inadequate to ensure a safe patient transfer by one person. This is because in maneuvering the patient onto beds of different heights, there is usually slippage between the bed structures when one person attempts the transfer. Thus, it is seen that, once again, two and probably three people would be required to safely effect a patient transfer in Jones. Other adjustable height wheelchair to bed structures are disclosed by Burke et al, U.S. Pat. No. 5,342,114, and Herbert et al, U.S. Pat. No. 5,179,745. These patented structures, like Crawford et al, above, are only able to be located next to the bed in which the patient is lying. Moreover, these prior art teachings, unlike Crawford et al, have no bungee cords to help hold the two bed structures together. Thus, a minimum of three people are seen needed to transfer a patient from one bed to the other.
The present invention is directed to a cantilevered mobile bed/chair that, while in its bed mode, is able to overhang a conventional thirty six inch width hospital type bed by up to half its width in cantilevered fashion so that a safe transfer of a patient can be effected, even by a single caregiver. After the transfer, the patient can then be transported by either remaining in the bed mode, or converted into a chair mode for further patient care. The objects of this invention are carried out by a unique lift structure providing cantilever support for a series of three hinged together platforms making up back, seat and foot portions of the chair/bed. The lift structure comprises a telescoping tower which mounts vertically on one side of a rectangular shaped wheeled base. The platforms comprise the patient support for the bed/chair, and are operatively coupled to an E-shaped frame structure that in turn is mounted in cantilever fashion horizontally from the telescoping tower controlled by a screw type jack associated therewith. While a screw jack is provided, it is obvious that other jacks such as hydraulic and scissors may be employed. With this offset tower and cantilever E frame design, the remote side (to the tower) of the platforms of the apparatus in the bed mode are able to overlap a hospital type bed by up to eighteen inches, or half the bed width of a conventional, thirty six inch wide hospital type bed. Thus, when it is desired to transfer a patient from or to a hospital type bed to the apparatus, the jack controlling the telescoping tower operates to raise the platforms above the bed, the apparatus wheeled over to overlap the bed by up to eighteen inches, and then lowered to press into the bed""s mattress. Moreover, the platforms comprising the bed are of a thin, highly strong material in which the side edges thereof are beveled or angled downward. This angle down design enables the platforms to further press into the mattress of the hospital type bed, not only ensuing that virtually no movement occurs therebetween, but that a substantially flat profile is presented for the two beds even with a one inch pad on the mobile bed. With such a relatively flat profile, and with the two beds locked in such a tight embrace, it becomes an easy matter for just one caregiver to manage a patient in a transfer procedure.
Although the lift mechanism of the invention can be carried out manually, the best mode comprises an electrically powered lift arrangement. That is, an electric motor is mounted to control a screw jack which is powered by a battery located at the wheeled base of the apparatus. The three platforms forming the head, seat and foot supports are connected by low profile piano hinges. Another electrically driven screw jack is mounted below the seat platform and controls the conversion of the bed into a chair configuration by way of levers and hinges. This second jack, like the first one, is mounted near the tower side of the unit so as to not interfere with the cantilevered overhang portion of the platforms. The chair mode may be under the control of either the caregiver or the patient, and features indefinite adjustment for patient comfort. In the case of immobilized patients, there is an auto seat reposition timer feature associated with the chair mode that periodically readjusts the sitting position to minimize bedsores. The seat platform includes a potty hole for increased patient maintenance. The wheeled base, besides providing support for the tower, accommodates, four, omni-directional wheels that may, in some models, be electrically powered; a hazard-free dry-cell, rechargeable battery and holder therefor; and a battery recharging unit. The back platform has provision for an oxygen bottle, while the foot platform includes an adjustable foot rest. The platforms comprising the bed include VELCRO straps for patient safety. The tower also accommodates an IV holder; combination food tray holder and arm rest that swings into position as needed; and a module for the auto seat reposition timer mentioned above.
Another object of the invention is to provide for a Trendelenburg position bed or where the bed is positioned to have the head lower than the feet. This is accomplished in the bed mode, one of several ways; one, by providing a multi-position gear and locking pin mechanism connected between the tower and E frame, or two, by way of a swing down jack mounted on the E frame. Thus, for example, in the case of the pin and gear arrangement, the pin is pulled and the E frame which is connected to the gear is rotated to be tilted to the desired position, and the pin reinserted to lock the bed in the Trendelenburg position.
A further object of the invention is to allow for portability of the apparatus by keeping the weight to about 160 pounds, yet of sufficient strength to support a load of up to 1500 pounds.
Other objects, features and advantages of the invention will be apparent from the following specification and drawings.